Nanotech thin-film advance reported

CHESTNUT HILL, Mass., June 7 (UPI) -- U.S. scientists say they've developed a "nanocoax" technology that can support a highly efficient thin-film solar cell that provides outstanding efficiency.

Boston College researchers said their nano-scale solar cell -- inspired by the coaxial cable -- offers greater efficiency than any previously designed nanotech thin-film solar cell. It does that, they said, by resolving the "thick and thin" challenge inherent to capturing light and extracting current for solar power.

The quest for high power conversion efficiency in most thin-film solar cells has been hampered by competing optical and electronic constraints -- a cell must be thick enough to collect a sufficient amount of light, yet it needs to be thin enough to extract current.

Boston College physicists said they resolved that challenge through a nanoscale solar architecture based on the coaxial cable -- a technology that dates to the mid 1800s.

"Many groups around the world are working on nanowire-type solar cells, most using crystalline semiconductors," Professor Michael Naughton, a co-author of the study, said. "This nanocoax cell architecture, on the other hand, does not require crystalline materials, and therefore offers promise for lower-cost solar power with ultrathin absorbers. With continued optimization, efficiencies beyond anything achieved in conventional planar architectures may be possible, while using smaller quantities of less costly material."

The research appears in the early online edition of the journal Physica Status Solidi.